/Engine/Source/Developer/SourceControl/Public/SourceControlHelpers.h
Helper function to branch/integrate packages from one location to another maintaining a relationship between the files in source control (when possible)
true if the file packages were successfully branched.
static bool BranchPackage ( [UPackage](API\Runtime\CoreUObject\UObject\UPackage) * DestPackage, [UPackage](API\Runtime\CoreUObject\UObject\UPackage) * SourcePackage, [EStateCacheUsage::Type](API\Developer\SourceControl\EStateCacheUsage__Type) StateCacheUsage )